Refrigerators generally have one or more pans for storing fresh vegetables and fruit. These pans are commonly referred to as crisper pans and their function is to create a storage environment having higher humidity than the rest of the refrigerator food compartment. Accordingly, in crisper pans, vegetables and particularly moist leafy vegetables do not dry out as they would if stored uncovered in the refrigerated food compartment.
Prior art crisper pans generally have side support lips which slidably engage guide channels or tracks on the underside of a shelf which also functions as a lid for the crisper pan. When a crisper pan is slid to its backward or closed position, the pan is completely sealed underneath the shelf. Accordingly, the dry cold air circulating in the refrigerated food compartment is prevented from flowing through the pan thereby reducing the humidity in the crisper pan. Stated differently, by providing a tight seal for the pan, moisture in the vegetables is prevented from escaping the pan to the rest of the refrigerated food compartment. Some prior art crisper pans have used gaskets to provide a substantially air-tight seal.
The prior art shows a recognition that too much moisture in a crisper pan may adversely affect vegetables and fruit. For example, if a large quantity of very moist vegetables is placed in a crisper pan, it is not unusual for the very high humidity in the crisper pan to cause condensation which drips down and forms puddles. It is well known that a soggy condition can cause vegetables to wilt or rot. Accordingly, it is known that it may be desirable to adjust or control the humidity in a crisper pan to a preferable range where the humidity is high enough to prevent vegetables from drying out but is low enough to prevent the formation of condensation and wilting.
One prior art approach to controlling the humidity in a crisper pan utilizes a lid with an inclined rib. Lateral movement of a slide control at the front of the crisper is transformed into forward or backward movement of the lid. In the backward position, an opening exists between the front of the lid and the front wall of the crisper pan; a back opening is created by the rib incline causing the lid to be elevated from the back wall of the crisper pan. Accordingly, the openings at the front and the back of the crisper pan are simultaneously varied in size to alter the amount of dry cold air flowing through the crisper pan. The apparatus of this approach, however, has disadvantages. First, the lid does not also function as a shelf because the operative principle requires that the lid be vertically moveable to adjust the humidity; accordingly, the lid is an extra part that is mounted under the bottom shelf. Not only does this involve extra cost and more complicated fabrication, but it also reduces available refrigerator storage space. Second, the parts and fabrication for an apparatus that transforms movement in one direction to an orthogonal direction is more complicated and expensive than one that does not. Further, it is subject to sticking and breaking.